Communication Circuit Troubleshooting
Cruise Control Communication Circuit TroubleshootingNOTE: After troubleshooting, perform the powertrain control module (PCM) idle learn procedure.
1. Start the engine.
2. Turn on the cruise control main switch, then drive the vehicle to speeds over 25 mph (40 km/h) with the cruise control.
Does the cruise control operate?
YES - Go to step 3.
NO - Check the cruise control unit or cruise control actuator.
3. Turn the ignition switch OFF.
4. Disconnect cruise control unit 14P connector and powertrain control module (PCM) connector A (32P).
5. Check for continuity between the No. 8 terminal of the cruise control unit 14P connector and body ground.
Is there continuity?
YES - Repair short to ground in the wire between PCM connector terminal A5 and the cruise control unit 14P connector terminal No. 8.
NO - Go to step 6.
6. Reconnect the cruise control unit 14P connector and PCM connector A (32P).
7. Connect a voltmeter between the No. 8 terminal of the cruise control unit 14P connector and body ground. Test-drive the vehicle at speeds over 25 mph (40 km/h) with the cruise control set, and watch the voltmeter.
Is there about 1 V?
YES - Go to step 8.
NO - Substitute a known-good cruise control unit. If the system works properly, replace the cruise control unit.
8. Connect a voltmeter between PCM connector terminal A5 and body ground. Drive the vehicle at speeds over 25 mph (40 km/h) with the cruise control set, and watch the voltmeter.
Is there about 1 V?
YES - Check for loose connectors of the BLU/GRN wire between the cruise control unit and PCM. If necessary replace the PCM and recheck.
NO - Repair open in the wire between the PCM connector terminal A5 and the cruise control unit 14P connector terminal No. 8.